Screw



FIG. 1 is a front view of a screw showing my new design;

FIG. 2 is a rear view thereof;

FIG. 3 is a left-side view thereof;

FIG. 4 is a right-side view thereof;

FIG. 5 is a top view thereof;

FIG. 6 is a bottom view thereof; and,

FIG. 7 is an enlarged partial sectional view taken along lines 7-7 of FIG. 1.

The broken line showing of the screw is intended for the purpose of showing environment and forms no part of the claimed design. 

The ornamental design for a screw, as shown and described. 